1. School of Computer Science and Engineering, Xi’an University of Technology, Xi’an, China
2. Department of Geography and Spatial Information Techniques, Ningbo University, Ningbo, China
3. Faculty of Electrical and Computer Engineering, University of Iceland, Reykjavík, Iceland
4. School of Electronical and Information Engineering, Shaanxi University of Science and Technology, Xi’an, China
5. Climate and Ecosystem Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA